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arXiv · 2402.01028

Directed graphs without rainbow stars

Daniel Gerbner·Andrzej Grzesik·Cory Palmer·Magdalena Prorok
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Abstract

In a rainbow version of the classical Turán problem one considers multiple graphs on a common vertex set, thinking of each graph as edges in a distinct color, and wants to determine the minimum number of edges in each color which guarantees existence of a rainbow copy (having at most one edge from each graph) of a given graph. Here, we prove an optimal solution for this problem for any directed star and any number of colors.

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Daniel Gerbner, Andrzej Grzesik, Cory Palmer, Magdalena Prorok. 2024-02-01. Directed graphs without rainbow stars. https://arxiv.org/abs/2402.01028

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